What Percentage of MtG Games are Decided Primarily by Mana Issues (Screw or Flood)?

My opponent mulled to 5 in game 1, dropped a Doomed Traveler, then scooped after he missed his second land drop (presumably out of frustration, though he was definitely not out of the game).

So given the freebee, we won a pretty evenly-matched game 2.

Game 3, my opener had 1 land. Unplayable. My mull to 6 had 1 land. Unplayable. It's at this point when I should be zen, but I friggin hate the game design. I mull to 5 to keep a crappy hand, but a better one that either of my first two.

It's really not a game at all. My opponent had mulled to 6, but on the draw that's far less impactful than playing a 5-card hand on the play. If you watch the video, you'll see that I get enough land to put down a Geist, but I lose any potential card advantage from Burning Oil due to his trick. I'm horribly behind on the board anyway. I drew 2 spells (Tragic Slip and Midnight Guard) and 6 lands the rest of the game. He invalidated my Slip with a Faith's Shield. So basically I was playing the entire third game crippled due to the mulligan, and flooded out anyway.

These types of matches are not fun. Not just because I lost, but because two of the games were not even played. They weren't games. They were non-games. I'm fine with game design that gives inferior players a chance to beat better players due to variance. But there are game designs that allow for that without having the experience be a complete waste of time. Poker is a good example of this. Even with horrible hole cards, I can still play the game in some meaningful way (e.g. bluffing). But MtG games that result from resource variance are simply unplayable, and thus un-fun.

My estimate for games decided by mana issues is about 20%. I initially estimated about 1 in 6, but I think it's slightly higher than that. And those experiences, while you should take them in stride, still leave a bad taste in my mouth, because I think they are not a necessary part of the game design.